Apparatus and method for continuous drying of laundry goods

ABSTRACT

A vertical tank into which the wet laundry goods, as loose pieces, are introduced. Heated air is introduced at the bottom and directed upwardly, into and through the goods. The air tends to lift the goods, and does so, progressively more so as the goods become more dry, and the dry goods are carried to the top, where they engage conveyor means which carries them laterally out through a side opening.

United States Patent 1191 Grantham 1 Dec. 17, 1974 1 [5 APPARATUS AND METHOD FOR 2,770,052 11/1956 Morrison 34 10 CONTINUOUS DRYING 0F LAUNDRY 2,903,800 9/1959 Skoglund 34/57 A X GOODS 3,186,102 6/1965 Brociner et al. 34/10 3,399,462 9/1968 Koch et a1. 34/57 A Inventor; Frederick W. Grantham, 600 S.

Lairport St., Santa Monica, Calif. 90245 Filed: Sept. 21, 1972 Appl. No.: 290,863

Related U.S. Application Data Primary ExaminerCharles J, Myhre Assistant Examiner-William C. Anderson Attorney, Agent, or Firm-Henry M. Bissell [57] ABSTRACT A vertical tank into which the wet laundry goods, as loose pieces, are introduced. Heated air is introduced at the bottom and directed upwardly, into and through the goods. The air tends to lift the goods, and does so, progressively more so as the goods become more dry, and the dry goods are carried to the top, where they engage conveyor means which carries them laterally out through a side opening.

10 Claims, 6 Drawing Figures PATENTEL 1 71974 3, 854.221

APPARATUS AND METHOD FOR CONTINUOUS DRYING OF LAUNDRY GOODS This application is a continuation-in-part of my prior and copending parent application, Ser. No. 16,318, filed Mar. 4, 1970 and now U.S..Pat. No. 3,693,382.

CROSS REFERENCES Applicants copending application which is also a continuation-in-part of the above parent application: Ser. No. 290,862 Filed Sept. 21, 1972 for Laundering Apparatus and Method, Continuous.

OBJECTS OF THE INVENTION Still another object is to provide a novel dryer which is ofcontinuous nature in that the wet goods are intro duced in a continuous stream, and after drying, the goods are removed from the dryer in a continuous stream, and in which a continuous air stream is introduced at the bottom of the dryer and flows upwardly; the wet goods because of their heavier weight remain toward the bottom of the dryer and as they begin to dry and lighten in weight, they are suspended in the air stream and are removed from the dryer adjacent the top thereof.

Still another object is to provide a continuous dryer of the kind just referred to having novel safety means for shutting off the fuel for heating the air stream, in the event that a momentary quantity of wet goods should be introduced into the dryer of greater quantity than the maximum air stream would be capable of lifting.

DESCRIPTION OF A PREFERRED EMBODIMENT In the drawings:

FIG. 1 is a side elevational view, partially diagrammatic in nature, of the novel dryer of the invention;

FIG. 2 is a view taken at line 2-2 of FIG. 1;

FIG. 3 is a view taken at line 3--3 of FIG. 1;

FIG. 4 is a view taken at line 4-4 of FIG. 3; FIG. 5 is a side elevational view of a dryer generally similar to that of FIG. 1 but showing a different form of heating means, and showing a recirculating means; and

FIG 6 is a top view of the device of FIG. 5.

The drawings illustrate a laundry dryer that is of continuous nature and is particularly adaptable for use in an overall continuous laundering apparatus, such as disclosed and claimed in the parent application. That application discloses several washing units which may be washing per se, rinsing, etc., an extracting component or unit and the drying component or unit disclosed and claimed herein.

The reference numerals used in the parent application are also used in the present application to identify the same elements.

In the present instance laundry goods are carried to the dryer by suitable means such as a conveyor 278, which in the parent application is the conveyor leading from the extractor component or unit. These goods are in the form of separate and detached pieces, as distinguished from long or continuous pieces. In conveying the pieces to the dryer of the present invention, they may be spaced apart, touching in a continuous line, or even overlapping, but when they are introduced into the dryer, they'become as pieces separated from each other.

Referring to the drawings in detail, FIGS. 1-6 show drying means identified in the parent application as the dryer or drying unit 58. The unit as represented in FIG. 1 includes a tank 272 having a main body portion 273, preferably cylindrical, and a hopper bottom portion 274. The tank has an inlet opening 276 through which the laundry goods 60 are introduced into the tank.

A burner unit 280 is provided for drying the goods in 1 the tank, this burner unit including a pressure blower 282 having an outlet line 284 leading into the bottom of the hopper portion of the tank. Leading to the blower is an air inlet line 286 and leading into that line is a gas line 288 having a control valve 290 controlled by a circuit means 292 which includes a switch means 294. The switch means includes a contactor lever 295 having an arm or vane 296 which has its inner end extending into the tank adjacent the bottom of the hopper portion 274 onto which the goods could fall as the latter are introduced into the dryer. The goods however may not fall onto it, but be suspended constantly thereabove by the draft of heated air, as referred to hereinbelow.

Upon operation of the burner unit 280 the heated air is delivered into the tank and it dries the goods; the goods are dried of course progressively and as the pieces of the goods are increasingly dried, they become lighter in weight and lifted by the air stream to a greater extent, while the wetter and heavier pieces remain closer to the bottom for additional drying. In this progressive drying operation, the dry pieces rise to the top a of the tank and are then removed therefrom by constantly running conveyor means indicated as a whole at 298, this conveyor means including a top conveyor belt 300 which preferably is of highly perforate nature to allow maximum flow of air therethrough. Also the width of this conveyor belt 300 may be substantially less than the diameter of the tank whereby to leave open spaces 302 (FIG. 6) at the sides for air to pass therethrough. The conveyor 300 preferably extends through the walls of the tank at least at its exit end where a portion 304 extends through an exit opening 310 (see also FIG. 1). Under the conveyor belt 300 is a shorter conveyor belt 306 and running in the opposite direction, the two conveyors having adjacent runs moving in the same direction, as indicated by the arrow 308. The lower conveyor belt 306 also preferably extends out through the opening 310 for assuring complete carrying out of the goods.

The dry pieces are lifted against the top conveyor 300 and are carried along thereby until they encounter the lower conveyor 306 and the two conveyors together grip the goods therebetween and carry them out from the tank through the exit opening 310 where they may for example slide down a stationary slide 312. If the goods engage the lower side of the lower conveyor belt 306 as they rise, the lower run thereof carries them to the left and the goods then engage the upper conveyor and are carried thereby in the manner referred to, namely, toward the lower conveyor, and the two conveyors then grip the goods and carry them out in the manner stated. Preferably a shield or guard 314 (FIGS. 3, 4) is provided, of any suitable type, but preferably in the form of a flexible apron, mounted on the exterior of the tank adjacent the outer end of the upper conveyor 300, and over the exit opening 310, this guard serving to confine the goods somewhat on the slide 312. The goods may then drop onto a final exit conveyor 316 to a suitable receptacle.

In the event that an unusually large quantity of wet goods should be introduced into the dryer, and of such great quantity that the air stream from the burner unit 280 should not be able to lift the goods and suspend them in the air, and the goods thus be in danger of being burned, the goods would fall on the lever or vane 296 and move it in clockwise direction, thereby lifting the contractor lever 295 and breaking the contact at the switch 294 and shutting off the gas supply, providing a safety factor in this direction.

FIG. 1 also shows outlet air lines 318, having dampers 320 therein, for controllably relieving the air from the interior of the tank, with screens 321 over their inner ends.

FIGS. 5 and 6 show a dryer similar to that represented in FIG. 1 but with a different heating arrangement and including recirculation means. The exit air lines 3118 connect with a common manifold 322 which communicates with a burner unit 324 which includes a housing 326. The manifold 322 also communicates with an exhaust air line 328 leading to an exhaust blower 330. At the juncture of the manifold 322, exhaust line 328, and housing 326, is a valve or damper 332 for controlling the distribution of the air in the manifold to the line 328 or the burner unit 324. The burner unit 324 includes a burner 334 firing in an area surrounded by a shell 336 within the housing 326. The housing 326 is provided with an inlet opening 338 preferably at a location around the shell 336, and leading from this area is an air inlet line 340 leading to the blower 282. j

The drying operation of this dryer of FIGS. 5, 6, is substantially identical with that of FIG. 1, Le, the heated air passes through the goods, gradually drying them, and carrying them to the top where they are carried out. However, in this case a portion of the air exhausted from the tank is recirculated, resulting in greater efficiency in the overall drying operation, the amount of recirculation being controlled by the valve 332.

I claim:

1. A method of continuously drying laundry goods, including the steps of:

continuously introducing the goods into a vertically oriented container;

introducing heated air at the bottom of the container and forcing the air upwardly therein and thereby raising the goods, and so continuously raising them higher as the goods become progressively drier and lighter;

raising only those goods which are sufficiently dry to warrant removal to a predetermined region adjacent the top of the container; and

continuously removing the dried goods from said region adjacent the top of the container by physically engaging said goods and conveying them out of the container.

2. A laundry dryer comprising:

a vertically arranged tank;

means for introducing laundry pieces to be dried into the tank;

air heating means;

means for introducing heated air at the bottom of the tank in such quantities as to lift the laundry pieces so introduced, an operative as the laundry pieces become drier and lighter to raise them higher in the tank, and when they become dry to raise them to the top of the tank; and

conveyor belt means at the top of the tank for physically engaging the dried pieces and conveying them out of the tank.

3. A laundry dryer according to claim 2 and including means responsive to the weight of the wet pieces at the bottom of the tank, and operative, in response to wet pieces above a predetermined weight being introduced into the tank which the stream of air is incapable of lifting, for shutting off fuel to the air heating means.

4. A laundry dryer according to claim 2, and including safety means adjacent the bottom of the tank, said safety means including an element extending into the interior of the tank positioned for heavy pieces to engage in the event such pieces fall to the bottom of the tank, and operative when so engaged by the pieces for disabling the means for introducing heated air into the tank.

5. A laundry dryer according to claim 2, wherein the conveyor belt means is in horizontal position and arranged for engagement by the pieces as they rise, and the conveyor belt means conveys the pieces horizontally out of the tank.

6. A laundry dryer according to claim 5 in which the conveyor belt means includes an upper conveyor extending a substantial distance across the tank and a lower conveyor of lesser length leaving a portion of the upper conveyor exposed to the interior of the tank and positioned for engagement by the pieces, and the conveyors have adjacent runs traveling in the same direction and constituting that conveyor belt means which is operative for engaging the pieces and so carrying them out of the tank.

7. A laundry dryer according to claim 6 wherein the upper conveyor extends substantially across the tank, and the lower conveyor is of substantially lesser length, leaving a substantial length of the upper conveyor exposed for engagement by the pieces, and the two conveyors terminate in a discharge opening at the side of the tank whereat they discharge the pieces conveyed from the tank.

8. A laundry dryer according to claim 7 wherein the dryer includes a downwardly inclined slide onto which the pieces drop upon being discharged from the conveyor opening, for controlling the location of the deposition of the pieces.

9. A laundry dryer according to claim 8 and including a guard extending downwardly over at least the upper portion of the slide, and over the side opening in the tank.

10. A laundry dryer according to claim 8 wherein the tank has an exit opening and the conveyors extend therethrough and the discharge opening thereof extends beyond the side of the tank.

it t t! 

1. A method of continuously drying laundry goods, including the steps of: continuously introducing the goods into a vertically oriented container; introducing heated air at the bottom of the container and forcing the air upwardly therein and thereby raising the goods, and so continuously raising them higher as the goods become progressively drier and lighter; raising only those goods which are sufficiently dry to warrant removal to a predetermined region adjacent the top of the container; and continuously removing the dried goods from said region adjacent the top of the container by physically engaging said goods and conveying them out of the container.
 2. A laundry dryer comprising: a vertically arranged tank; means for introducing laundry pieces to be dried into the tank; air heating means; means for introducing heated air at the bottom of the tank in such quantities as to lift the laundry pieces so introduced, an operative as the laundry pieces become drier and lighter to raise them higher in the tank, and when they become dry to raise them to the top of the tank; and conveyor belt means at the top of the tank for physically engaging the dried pieces and conveying them out of the tank.
 3. A laundry dryer according to claim 2 and including means responsive to the weight of the wet pieces at the bottom of the tank, and operative, in response to wet pieces above a predetermined weight being introduced into the tank which the stream of air is incapable of lifting, for shutting off fuel to the air heating means.
 4. A laundry dryer according to claim 2, and including safety means adjacent the bottom of the tank, said safety means including an element extending into the interior of the tank positioned for heavy pieces to engage in the event such pieces fall to the bottom of the tank, and operative when so engaged by the pieces for disabling the mEans for introducing heated air into the tank.
 5. A laundry dryer according to claim 2, wherein the conveyor belt means is in horizontal position and arranged for engagement by the pieces as they rise, and the conveyor belt means conveys the pieces horizontally out of the tank.
 6. A laundry dryer according to claim 5 in which the conveyor belt means includes an upper conveyor extending a substantial distance across the tank and a lower conveyor of lesser length leaving a portion of the upper conveyor exposed to the interior of the tank and positioned for engagement by the pieces, and the conveyors have adjacent runs traveling in the same direction and constituting that conveyor belt means which is operative for engaging the pieces and so carrying them out of the tank.
 7. A laundry dryer according to claim 6 wherein the upper conveyor extends substantially across the tank, and the lower conveyor is of substantially lesser length, leaving a substantial length of the upper conveyor exposed for engagement by the pieces, and the two conveyors terminate in a discharge opening at the side of the tank whereat they discharge the pieces conveyed from the tank.
 8. A laundry dryer according to claim 7 wherein the dryer includes a downwardly inclined slide onto which the pieces drop upon being discharged from the conveyor opening, for controlling the location of the deposition of the pieces.
 9. A laundry dryer according to claim 8 and including a guard extending downwardly over at least the upper portion of the slide, and over the side opening in the tank.
 10. A laundry dryer according to claim 8 wherein the tank has an exit opening and the conveyors extend therethrough and the discharge opening thereof extends beyond the side of the tank. 